Re: [PATCH 1/2] drm/nouveau: fix stale locked mutex in nouveau_gem_ioctl_pushbuf

From: Danilo Krummrich <dakr@redhat.com>
To: Karol Herbst <kherbst@redhat.com>, linux-kernel@vger.kernel.org
Cc: Lyude Paul <lyude@redhat.com>,
	dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org
Subject: Re: [PATCH 1/2] drm/nouveau: fix stale locked mutex in nouveau_gem_ioctl_pushbuf
Date: Tue, 5 Mar 2024 10:18:38 +0100	[thread overview]
Message-ID: <deaeaceb-bfb0-4dbf-b800-b0debfd3bac9@redhat.com> (raw)
In-Reply-To: <20240304183157.1587152-1-kherbst@redhat.com>

On 3/4/24 19:31, Karol Herbst wrote:
> If VM_BIND is enabled on the client the legacy submission ioctl can't be
> used, however if a client tries to do so regardless it will return an
> error. In this case the clients mutex remained unlocked leading to a
> deadlock inside nouveau_drm_postclose or any other nouveau ioctl call.
> 
> Fixes: b88baab82871 ("drm/nouveau: implement new VM_BIND uAPI")
> Cc: Danilo Krummrich <dakr@redhat.com>
> Signed-off-by: Karol Herbst <kherbst@redhat.com>

Should add a stable tag for that one, otherwise:

Reviewed-by: Danilo Krummrich <dakr@redhat.com>

> ---
>   drivers/gpu/drm/nouveau/nouveau_gem.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c
> index 49c2bcbef1299..5a887d67dc0e8 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_gem.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
> @@ -764,7 +764,7 @@ nouveau_gem_ioctl_pushbuf(struct drm_device *dev, void *data,
>   		return -ENOMEM;
>   
>   	if (unlikely(nouveau_cli_uvmm(cli)))
> -		return -ENOSYS;
> +		return nouveau_abi16_put(abi16, -ENOSYS);
>   
>   	list_for_each_entry(temp, &abi16->channels, head) {
>   		if (temp->chan->chid == req->channel) {